I don't think you'd get too many arguments from rational people if you said it takes a special kind of stupid to take to social media to disparage a mother - albeit a famous one - for kissing her young daughter on the lips on her birthday. That said, I think close to the same amount of people that agree with that assessment would also agree that kissing your child on the lips is weird. It's not inconceivable. It's not disgusting. It's not homoerotic. It's not wrong. It's just...weird.
That's as close as something can be to a fact while still being an opinion by definition. If you don't think touching lips with your parents is weird than you've probably spent your entire life touching lips with your parents and everyone around you has been giving you weird ass looks. The more I think about it this feels like something the most Italian of Italian families do, and everyone knows that Italians are WEIRDLY close with their family. I can just imagine being a kid hanging out in my friend's kitchen watching his mother kiss him on the lips and tell him to "be safe" while playing outside. You know what I would do the second we got outside? Probably push him in the grass and call him a "gross weirdo", because any friend that wouldn't verbally acknowledge how weird it is isn't a friend at all. Granted it's a little more acceptable when it's a mother on daughter kiss, but that's far from completely removing it from the realm of weirdness. Victoria Beckham is a celebrity whose married to a celebrity so it's safe to say they do things a bit differently, but "differently" might as well be a synonym for "weirdly".
At least there's a gang of internet civilians who have her back so she can feel less weird about clearly being weird...